Portable urethane spray gun

ABSTRACT

A portable urethane spray gun is disclosed. The apparatus includes a structure for controlling the discharge of the components of the urethane, thoroughly mixing the components of the urethane and purging the spray gun of one of the components by stopping the flow of the other of the components prior to stopping the flow of the purging component thereby providing for dispensing of urethane without the use of compressed air for atomization or purging.

United States Patent [191 Price Nov. 18, 1975 PORTABLE URETHANE SPRAY GUN [75] Inventor: Sidney M. Price, Bel Air, Md.

[73] Assignee: Erie Industrial Insulation Corporation, McKean, Pa.

[22] Filed: June 3, 1974 [21] Appl. No.: 475,602

[52] US. Cl. 239/403; 239/414; 239/416 [51] Int. Cl. B05B 7/12; F23D 13/38 [58] Field of Search 239/399, 525, 526, 414, 239/416, 403; 222/135 [56] References Cited UNTTED'STATES PATENTS 3,144,210 8/1964 Levy 239/403 3,232,540 2/1966 Cassanmagnago.....

3,375,978 4/1968 Rennie 239/113 3,409,044 11/1968 Sobek et a1. 239/414 3,595,482 7/1971 Loveday 239/403 3,726,634 4/1973 Thomson et a1, 239/403 3,790,030 2/1974 lves 239/414 Primary Examiner-Lloyd L. King [57] ABSTRACT A portable urethane spray gun is disclosed. The apparatus includes a structure for controlling the discharge of the components of the urethane, thoroughly mixing the components of the urethane and purging the spray gun of one of the components by stopping the flow of the other of the components prior to stopping the flow of the purging component thereby providing for dispensing of urethane without the use of compressed air for atomization or purging.

3 Claims, 8 Drawing Figures U.S. Patent Nov. 18, 1975 Sheet 2 of2 3,920,188

/IIO

PORTABLE URETHANE SPRAY GUN BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to the spraying of urethane foam onto desired surfaces, into areas and wherever desired, which is portable in nature and provided with a unique arrangement of structure for providing a supply of urethane components, mixing and spraying the components, with the arrangement being such that the spraying device will be purged to eliminate hardening or solidification of the mixed components in the spraying device.

2. Description of the Prior Art Devices for spraying two fluid component materials are known in which the components are mixed prior to discharge or subsequent to discharge. Prior US. Pat. No. 3,179,341, issued Apr. 20, 1965, is exemplary of such devices and this patent also discusses the development of the prior art in this field. Additional patents exemplary of spray guns are US. Pat. Nos: 3,232,540, issued Feb. I, 1966, and 3,375,978, issued Apr. 2, 1968. Such devices have generally required the use of compressed air for thorough mixing and atomization of the two components or for purging the spraying device and, in some instances, employ a solvent for purging. While known devices have been used to some degree of success, considerable problems still exist in providing a portable urethane spraying system, heating the components under accurate control and spraying the mixed components with a spray gun and purging the spray gun after use.

SUMMARY OF THE INVENTION The urethane spray system of this invention incorporates two conduits extending from each of the supply tanks which are each provided with a heater for maintaining the temperature of the components within de- 1 sired limits and each conduit is also provided with a flow valve and the conduits are connected with a spray gun. The spray guns are provided with nozzles that are virtually self-cleaning and shutoff valves that require a minimum of maintenance.

OBJECTS OF THE INVENTION An object of the invention is to provide a portable urethane system employing a spray gun that does not require any external air or any solvent purge to operate in a continuous manner with the spray gun including a nozzle structure that will thoroughly mix and dispense two components of the urethane in a manner to enable the mixed urethanes to be placed in voids for the purpose of insulation or floatation or discharged in an atomized spray pattern onto a surface.

Another object of the invention is to provide a urethane spray gun which is effective in operation, accurate in control, efficient in operation, easy to use and maintain and relatively inexpensive in manufacture and operation with the device being constructed so tha portability thereof is maintained.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had GENERAL DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view of the gun according to the invention.

FIG. 2 is a transverse, sectional view, on an enlarged scale, taken substantially upon a plane passing along section line 2-2 of FIG. 1 illustrating further structural details of the gun.

FIG. 3 is a vertical sectional view taken substantially upon a plane passing alongv section line 33 of FIG. 2 illustrating the structural details of the spray gun.

FIG. 4 is an enlarged view of a part of the nozzle.

FIG. 5 is a front viewof the inner nozzle part with the outer part removed, taken at line 5-5 of FIG. 4.

FIG.v 6 is a front cross sectional view similar to FIG. 3 of another embodiment of the invention showing the block for the gun.

FIG. 7 is an enlarged view of one of the shutoff members.

FIG. 8 is a cross sectional view taken on line 8-8 of FIG. 6.

DETAILED DESCRIPTION OF THE DRAWINGS Now with more particular reference to the drawings and referring now specifically to FIGS. 1-5 of the drawings, the spray gun 10 includes a block 12 supported in depending relation to a generally T-shaped plate 13 by fastener bolts 21. The T-shaped plate 13 has a narrow shank extending perpendicularly from one edge portion of the transverse part of the plate 13, as illustrated in FIG. 1, and includes a depending hand grip 11 secured to the end portion thereof by fastener bolts 20 with the hand grip 11 generallybeing parallel to but spaced from the block 12 with the hand grip adapted to be received in the palm portion of the hand and to be engaged by the fingers for supporting the spray gun 10 for manipulation thereof in the usual manner of supporting and manipulating a spray gun device.

Mounted in the block 12 is a nozzle assembly, generally designated by the numeral 22, with the nozzle assembly being controlled by an elongated control rod 15 that is reciprocally received in a bore 23 in the block 12 and which extends toward the hand grip 11. The rod 15 extends loosely through a slot 24 in an actuating handle 14 which depends from a transverse pivot pin 25 received in a recess 26 in the bottom surface of an intermediate portion of the frame 13 whereby the actuating handle 14 is disposed between the frame 13 and the hand grip 11 and adjacent the hand grip 11 so that the fingers of a person manipulating the spray gun may easily grip the actuating handle 14 to pivot it toward the hand grip 11 which moves the control rod 15 toward the hand grip 11. The slot 24 in the actuating handle 14 provides a space for the control rod 15. The end of the the control rod 15 and the other end engaging an adjustable externally threaded set screw 30 which forms a to the accompanying drawings forming a part hereof,

wherein like numerals refer to like parts throughout.

closure for the bore 28 and an adjustable abutment for the spring 29 thereby enabling the closing bias of the spring on the control rod 15 to be varied. Thus the spring 29 will bias the control rod to a normal position toward the nozzle assembly 22 and will also return the actuating handle 14 to its normal position spaced away from the hand grip 1 1. The pins 31 and 32 extend through control rod 15 and one pin 31 and 32 will engage each side of the actuating handle 14.

The nozzle assembly 22 includes an end cap 18 that may be of generally cylindrical construction and provided with threads 34 on the inner end thereof for, threading into a threaded recess 33 in the block 12. Opposed side edges of the end cap 18 are preferably flattened at 35 to facilitate threading and unthreading of the end cap 18 in that the flat portions 35 provide for easier gripping thereof or enable a wrench to be employed for assembling and disassembling of the nozzle assembly. Also, the end cap 18 is provided with a passageway or orifice 36 extending longitudinally there-, through with the inner end of the end cap receiving the outernozzle part 17.

The outer nozzle part 17 has an outer cylindrical part 37 which has a tube 38 integrally fixed thereto. The nozzle part 17 may be made of Teflon or other suitable material, as may the inner nozzle part 16. The conical nozzle part 16 has a cylindrical part 44 that terminates V in the frusto-conical -end 40. Cylindrical part 44 is snugly received in bore 58 in block 12.End 40 forms a seal with the surface of the internal conical end 39 on the outer nozzle part 17. The inner nozzle part 16 has a bore 45 that receives the locating pin 46 thereby holding the inner nozzle part 16 in proper location so that the bores 48 and 49 will connect to bores 52 and 53 in the block 12. Bores 52 and 53 communicate through lateral bores 54 and 55 with the threaded bores 56 and 57 that receive the hose fittings '58 and 59 connected respectively to two parts of the material being sprayed. The inner nozzle part 16 also has a central bore 47 which slidingly receives the control rod 15 and is slightly smaller than the control rod 15 so that the control rod 15 forms slidingengagement with the bore 47 and thus provides a seal preventing the escape of material. Spaced bores 48 and 49 extend through the nozzle part 16 and terminate at 40. The bores 48 and 49 communicate with bores 52 and 53 in the block 12, whichin turn communicate with bores 56 and 57, as aforesaid.

Tangential bores 50 and 51 in inner noule part 16 communicate from bores 48 and 49 and with the central bore 47. Bores 50 and 51 are offset from the center diameter of the inner nozzle part 16 and extend toward the center of the inner nozzle part 16'and toward the,

conical end 40. It will be noted that the bore 50 is disposed closer to the conical surface 40 than the bore 51.

ing an innernozzle part as in the embodiment of FIGS.

l-S. Openings 160 and 161 through the head are intended to register with bores such as 48 and 49'inanozzle part, such as shown in FIGS. 4 and 5., Lateral bores 163 and 164 communicate with bores and 161 and threaded counterbores 155 and 156 communi-. cate with bores 163 and 164. A supply of the material.

to be. sprayed, which include a first material and a second material, are intended to be connected by suitable y hose connections tothreaded counterbores 156 and 157 which have continuation bores 154 and 155 that, communicate with the bores 163 and 164. The;

threaded nuts 168 are received in the threaded counjterbores 165 and 166 and these nuts 168 have an unthreaded bore 169 that receives the rods 170. Rods 17,0 1 are connected attheir outer. ends to handles 171 and are freely rotatable in bores 169. A Teflon insert 180 is disposed in a counterbore in the inner end of the nut 168 and provides a seal. Therod 170 hasan axial hole 172 which communicates with a lateral hole 173. The rod 170 extends through the bore 163 and the hole 173 is disposed adjacentthe hole 154. Thus when the handle 171 is rotated to, the position shown in FIG. 6, the I hole 163 registers with the hole 154 so that material canflow from the tank connected to the threaded counterbore 156 through the bore 154, lateral hole 173,the axial bore 172 and the bore 163 to the hole i I 160 and out through bore 48, bore 50 and bore 41 through the nozzle. When the handle 171 is rotated to the position atright angles to the position shown in FIG. 6, the hole 173 will be out of alignment withthe bore 154 so that no materialcan flow. A Teflon insert 174 provides a seal around the rod 170 to prevent the leakage of material. A collar 181 is attached to rod 170 and limits its outward movement. Cleanout holes 183.

are formed in body 12. Holes 183 align with hole 173in rod 170 when the rod is rotated to OFF position. Thus an instrumentcan be inserted through bores 183 into The embodiments of the invention in which an. exclu- A sive property or privilege is claimed are defined as follows: i

1. A spray gun and nozzle combination comprising, Y

a nozzle forprojecting a spray made up of two components comprising,

an inner nozzle member made of a material having the resilient and frictional properties of Teflon,

having an outer generally conical end and a central bore,

two laterally. disposed bores in said inner 'nozzle' member,

two tangential bores each communicating with a said I lateral bore and extending inwardly therefrom and toward said conical end and terminating in said central bore whereby material from each of said lateral bores is projected into said central bore in a tangential path and mixes therein,

an outer nozzle member is disposed oversaid inner nozzle member, said outer nozzle member having a concave conical end nesting on said inner nozzle member and hav- 7 ing a central bore tapering from said conicalsurface to a small orifice,

a central rod extending through said central bore in said inner nozzle member,

said control rod having trigger means attached thereto, 1

said control rod making sliding and sealing engagement with the inner surface of said central bore, thereby providing a seal preventing the escape of material.

2. The combination recited in claim 1 wherein said inner nozzle member has a cylindrical outside surface,

and said cylindrical part is disposed in a cylindrical cavity in a head.

3. In combination, a spray gun and a nozzle and a shutoff means,

said spray gun having a block,

a central bore in said block,

said central bore receiving said nozzle,

an axial bore through said nozzle,

and a control rod extending through said axial bore,

a tangentially disposed bore in said nozzle,

a lateral bore in said block communicating with said tangential bore,

a counterbore communicating with said lateral bore,

said counterbore having a Teflon insert,

a central bore through said Teflon insert communicating with said lateral bore in said block,

a central rod slidably received in said central bore providing a seal with said Teflon material,

and a lateral bore in said Teflon insert having a supply of material to be sprayed through said nozzle connected thereto,

a rod extending through said Teflon insert,

said rod having an axial bore and an elongated lateral bore extending diammetrically through said rod communicating with said axial bore therein,

said rod having handle means thereon for rotating said rod to align said elongated lateral bore with said material supply thereby connecting said material supply with said tangential bore in said nozzle,

said rod being rotatable to'bring said elongated lateral bore therein out of alignment with said material supply whereby said material supply is shut off,

said block has a second lateral bore disposed generally at right angles to said first lateral bore and at right angles to said rod,

said second lateral bore communicating with said axial bore in said insert whereby said second lateral bore is in alignment with said elongated bore when said rod is rotated to bring said elongated bore out of alignment with said material supply whereby a tool may be inserted in said second lateral bore for cleaning said elongated bore,

said rod has a handle and a pointer on said handle,

said pointer being adapted to cooperate with means on said block to shut off the flow of material to said nozzle. 

1. A SPRAY GUN AND NOZZLE COMBINATION COMPRISING: A NOZZLE FOR PROJECTING A SPRAY MADE UP OF TWO COMPONENTS COMPRISING AN INNER NOZZLE MEMBER MADE OF A MATERIAL HAVING THE RESILIENT AND FRICTIONAL PROPERTIES OF TEFLON, HAVING AN OUTER GENERALLY CONICAL END AND A CENTRAL BORE, TWO LATERALLY DISPOSED BORES IN SAID INNER NOZZLE MEMBER, TWO TANGENTIAL BORES EACH COMMUNICATING WITH A SAID LATERAL BORE AND EXTENNDING INWARDLY THEREFROM AND TOWARD SAID CONICAL END AND TERMINATING IN SAID CENTRAL BORE WHEREBY MATERIAL FROM EACH OF SAID LATERAL BORES IS PROJECTED INTO SAID CENTRAL BORE IN A TANGENTIAL PATH AND MIXEX THEREIN, AN OUTER NOZZLE MEMBER IS DISPOSED OVER SAID INNER NOZZLE MEMBER. SAID OUTER NOZZLE MEMBER HAVING A CONCAVE CONICAL END NESTING ON SAID INNER NOZZLE MEMBER AND HAVING A CENTRAL BORE TAPERING FROM SAID CONICAL SURFACE TO A SMALL ORIFICE, A CENTRAL ROD EXTENDIING THROUGH SAID CENTRAL BORE IN SAID INNER NOZZLE MEMBER, SAID CONTROL ROD HAVING TRIGGER MEANS ATTACHED THERETO, SAID CONTROL ROD MAKING SLIDING AND SEALING ENGAGEMENT WITH THE INNER SURFACE OF SAID CENTRAL BORE, THEREBY PROVIDING A SEAL PREVENTING THE ESCAPE OF MATERIAL.
 2. The combination recited in claim 1 wherein said inner nozzle member has a cylindrical outside surface, and said cylindrical part is disposed in a cylindrical cavity in a head.
 3. In combination, a spray gun and a nozzle and a shutoff means, said spray gun having a block, a central bore in said block, said central bore receiving said nozzle, an axial bore through said nozzle, and a control rod extending through said axial bore, a tangentially disposed bore in said nozzle, a lateral bore in said block communicating with said tangential bore, a counterbore communicating with said lateral bore, said counterbore having a Teflon insert, a central bore through said Teflon insert communicating with said lateral bore in said block, a central rod slidably received in said central bore providing a seal with said Teflon material, and a lateral bore in said Teflon insert having a supply of material to be sprayed through said nozzle connected thereto, a rod extending through said Teflon insert, said rod having an axial bore and an elongated lateral bore extending diammetrically through said rod communicating with said axial bore therein, said rod having handle means thereOn for rotating said rod to align said elongated lateral bore with said material supply thereby connecting said material supply with said tangential bore in said nozzle, said rod being rotatable to bring said elongated lateral bore therein out of alignment with said material supply whereby said material supply is shut off, said block has a second lateral bore disposed generally at right angles to said first lateral bore and at right angles to said rod, said second lateral bore communicating with said axial bore in said insert whereby said second lateral bore is in alignment with said elongated bore when said rod is rotated to bring said elongated bore out of alignment with said material supply whereby a tool may be inserted in said second lateral bore for cleaning said elongated bore, said rod has a handle and a pointer on said handle, said pointer being adapted to cooperate with means on said block to shut off the flow of material to said nozzle. 